Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4889200 | Rock drill | — | 1989-12-26 |
| 4883135 | Apparatus for rock drill | Wolfang Peetz, Hermann Hugger | 1989-11-28 |
| 4852670 | Drilling tool with an exchangeable feed helix | Wolfgang Peetz | 1989-08-01 |